Tootpost-boe



E. Fr-G. GIBBS. TOOL PGST BORING BAR HOLDER.

APPLICATION FILED OCT. xsrma.

Patented July 1, 1919.

Wiiuws as lathes, and which hold,in turn, boring bars, 1

ToaZZ whom it may concern M UNITED STATES PATENT OFFICE a ToonrosriJ Bonme-niinnonnnn. Q

. mi Be it known that I, EDWARD F;-Gr. GIBBS,

a citizen of the United States, Eresidingat Washington, in theDistrict ofColumbia,

have invented certain newand useful 11 1- provements in Tool Post'Boring Bar"Holders, of which the following is a specification; My invention relates to improvements in i that class of boring bar holders which are held in the tool posts of commonfiengine which bars hold initurn inserted cutters, or

the tools usedfor boring netalsr It is hereinafter fully described shown in the ac? companying drawing and then specifically defined in the appended claims ii The specifieobj ects of this invention are to obtain a one-piece holder, ofthe char-h acter described; which allows the supporting tool post wedge to come as near-the strain receiving cutter point as brings the said cutter point directlyin front of the'said toolpost wedgegcarries a long open-ended barrel, the hollow of which constitutes a horizontally elongated, barholding aperture, whose apex is turned tomechanism illustrated in the accompanying drawing, which forms a part of this specification, and in which drawing- Figure l is a plan view of theholder held in a tool post of the usual type and holding a bar in working position. i

Fig. 2 is a front end elevation, showing a section of the bar on line 2-2 of Fig.1.

Fig. 3 is a side elevation; and

Fig. 4 is a section of the barrel only, on line w-w, of Fig. 2. a

Reference now being had to the details of the drawing by letters, in which similar-let ters refer to similar parts throughout the several views- A designates the stock, or shank, a straight bar of rectangular cross-sectional figure by which the holder is held in the tool post; a designates the neck which connects the stock and barrel referred to later; and a the very acute angular opening which separates the stock and barrel from their rear ends to the neck.

possible; Ewhich Specification o t e e Patented July 1,1919. Applicatienfiledbctohr 15,1915. Seria1No.55,999. i

B designates the open barrel; 6 designates the bar-holding aperture; 5 the chamberedrecess, and .79 the set screw lugs.

C designates the set screws which hold the bar in the aperture;

D designates the boring bar; a a E designates the inserted cutter or tool; O designates the tool post;

P lesignates the tool post wedge and 19 its widthgdimensionjlines projected;

Q designates the toolfpost ring. j

It is'tobe S6611tlliltythGStOCkpA, and barholdin'g IIlBll1b6lf',OI barrel, B, integral in this case,are parallelly disposedindirectly connected at. their front ends, which ends coincide, by the intervening neck a, all of This opening allows the stock to pass through the tool post, 0, until its front end comesbackto the front end of the tool post wedge, P, upon whichit bears. This construction brings the hearing as near the point of the strain receiving cutter E, as possible.

There are three objects in View in making the openinga slightly angular; the Wedge, P, being parallel tothestock,A,"and the bar, D, parallel to the barrel B, the acutenessof theangularitybf the openin a throws the strain-receiving point of the cutter E, immediately in front of the wedge to its maximum extent as shown by the projected lines, p; it makes a wide opening at the rear end of the barrel and shortens the neck,a. It is to be noted that the holder body, or the whole integral subject of my construction is a one-piece tool. a

bar as the size of the hole he is boring increases, without the holder.

It is further to be seen from Fig. 2 that the apex of the aperture or bar seat is turned toward the stock, While the setlowering the elevation of i screws, 0, enter through lugs b from the o posite side and force the bar as near t e tool post as possible, thus insuring greater rigidity.

It is also to be seen from all the figures,

especially Fig. 2, that the bars bearings consist of three contact points of triangular position at each end of the aperture, one of which is the set screw forcing the bar against opposite walls in the aperture.

And it is further to be noted that the bar bearsat the" ends of th'e'aperture rather than in the center because of the chambered recess, 6 shown in Figs. 2 and 4:.

Rigidity; the most important element in a boring tool is augmented by each of several featurcs of the holder which cooperate to that end; as follows ;the forward position of the neck, and the deep opening between the stock andthe barrel, which makes the minimum distance from strain to resistance, or from the cutter-point to the tool post wedge bearing, possible; the long distance between the bar-bearings inthe barrel; the

slightly angular character of thesaid opening; j the solid character of the. one-piece holder; and the direction of the apex of the bar aperture toward the stock.

The construction of this one-piece holder also makes for economy in manufacture.

Having thus fully describedmy invention, I desire to secure by Letters Patent what is new according to thefollowing claims:

1=. As an article of manufacture, a one piece tool-post boring-bar holder body; comprising a stock; and a barrel beginning on a common plane, indirectly; connected 'at their front ends by an intervening neck integral with both;--'and having. a slightly angular opening betweenthe said stock and barrel: from the said neck to the rear end of the barrel; all substantially as set forth.

2. A tool post boring bar holder; comprisinga stock; and a-barrel;connecte d at their front ends by a neck integral with both, all

Copies of this patent may be. obtained for of which, stock, neck and barrel begin on a line perpendicular to the axis of a barholdin-g aperture throughthe said barrel; and having a slightly angular opening between the said stock and barrel from the said neck to the rear end of the barrel; and means for holding a boring bar rigidly in the said aperture; all substantially as set forth.

3. A tool post boring bar holder, comprising astock; and abarrel; connected at their front ends by a neck integral with both, all of which, stock, neck and barrel begin on a line perpendicular to the axis of a bar holding aperture through the said barrel; and having a deep slightly angular opening between the said stock and barrel from the said neck to the rear end of the barrel; and a set screw near each end of the said barrel for holding a boring bar rigidly in the said aperture; all substantially as set forth.

4. Atool post boringbar holder, comprising a stock; and abar-holdin member; indirectly connected at their front ends by an intervening neck integral with both, all of which'stock, neck and member begin on aline perpendicular to the bar seat of the said member; and having a deep slightly angular opening between the said stock and member from the neck to the rear end of the said member; and means for holding a boring bar in the said bar seat, by forcing it in a horizontal direction, and toward the said stock; all substantially as set forth.

In testimony whereof I afiix my signature in presence of two witnesses.

, EDWARD F-G. GIBBS.

Witnesses:

A. L. HoUeH, A. R. FOWLER.

five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

